function strip_tags (str, allowed_tags) {
    // http://kevin.vanzonneveld.net
    // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   improved by: Luke Godfrey
    // +      input by: Pul
    // +   bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   bugfixed by: Onno Marsman
    // +      input by: Alex
    // +   bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +      input by: Marc Palau
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +      input by: Brett Zamir (http://brett-zamir.me)
    // +   bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   bugfixed by: Eric Nagel
    // +      input by: Bobby Drake
    // +   bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   bugfixed by: Tomasz Wesolowski
    // *     example 1: strip_tags('<p>Kevin</p> <br /><b>van</b> <i>Zonneveld</i>', '<i><b>');
    // *     returns 1: 'Kevin <b>van</b> <i>Zonneveld</i>'
    // *     example 2: strip_tags('<p>Kevin <img src="someimage.png" onmouseover="someFunction()">van <i>Zonneveld</i></p>', '<p>');
    // *     returns 2: '<p>Kevin van Zonneveld</p>'
    // *     example 3: strip_tags("<a href='http://kevin.vanzonneveld.net'>Kevin van Zonneveld</a>", "<a>");
    // *     returns 3: '<a href='http://kevin.vanzonneveld.net'>Kevin van Zonneveld</a>'
    // *     example 4: strip_tags('1 < 5 5 > 1');
    // *     returns 4: '1 < 5 5 > 1'

    var key = '', allowed = false;
    var matches = [];
    var allowed_array = [];
    var allowed_tag = '';
    var i = 0;
    var k = '';
    var html = '';

    var replacer = function (search, replace, str) {
        return str.split(search).join(replace);
    };

    // Build allowes tags associative array
    if (allowed_tags) {
        allowed_array = allowed_tags.match(/([a-zA-Z0-9]+)/gi);
    }

    str += '';

    // Match tags
    matches = str.match(/(<\/?[\S][^>]*>)/gi);

    // Go through all HTML tags
    for (key in matches) {
        if (isNaN(key)) {
            // IE7 Hack
            continue;
        }

        // Save HTML tag
        html = matches[key].toString();

        // Is tag not in allowed list? Remove from str!
        allowed = false;

        // Go through all allowed tags
        for (k in allowed_array) {
            // Init
            allowed_tag = allowed_array[k];
            i = -1;

            if (i != 0) { i = html.toLowerCase().indexOf('<'+allowed_tag+'>');}
            if (i != 0) { i = html.toLowerCase().indexOf('<'+allowed_tag+' ');}
            if (i != 0) { i = html.toLowerCase().indexOf('</'+allowed_tag)   ;}

            // Determine
            if (i == 0) {
                allowed = true;
                break;
            }
        }

        if (!allowed) {
            str = replacer(html, "", str); // Custom replace. No regexing
        }
    }

    return str;
}

function rawurlencode(str) {
    // http://kevin.vanzonneveld.net
    // +   original by: Brett Zamir (http://brett-zamir.me)
    // +      input by: travc
    // +      input by: Brett Zamir (http://brett-zamir.me)
    // +   bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +      input by: Michael Grier
    // +   bugfixed by: Brett Zamir (http://brett-zamir.me)
    // +      input by: Ratheous
    // +      reimplemented by: Brett Zamir (http://brett-zamir.me)
    // +   bugfixed by: Joris
    // +      reimplemented by: Brett Zamir (http://brett-zamir.me)
    // %          note 1: This reflects PHP 5.3/6.0+ behavior
    // %        note 2: Please be aware that this function expects to encode into UTF-8 encoded strings, as found on
    // %        note 2: pages served as UTF-8
    // *     example 1: rawurlencode('Kevin van Zonneveld!');
    // *     returns 1: 'Kevin%20van%20Zonneveld%21'
    // *     example 2: rawurlencode('http://kevin.vanzonneveld.net/');
    // *     returns 2: 'http%3A%2F%2Fkevin.vanzonneveld.net%2F'
    // *     example 3: rawurlencode('http://www.google.nl/search?q=php.js&ie=utf-8&oe=utf-8&aq=t&rls=com.ubuntu:en-US:unofficial&client=firefox-a');
    // *     returns 3: 'http%3A%2F%2Fwww.google.nl%2Fsearch%3Fq%3Dphp.js%26ie%3Dutf-8%26oe%3Dutf-8%26aq%3Dt%26rls%3Dcom.ubuntu%3Aen-US%3Aunofficial%26client%3Dfirefox-a'

    str = (str+'').toString();

    // Tilde should be allowed unescaped in future versions of PHP (as reflected below), but if you want to reflect current
    // PHP behavior, you would need to add ".replace(/~/g, '%7E');" to the following.
    return encodeURIComponent(str).replace(/!/g, '%21').replace(/'/g, '%27').replace(/\(/g, '%28').replace(/\)/g, '%29').replace(/\*/g, '%2A');
}

function rawurldecode(str) {
    // http://kevin.vanzonneveld.net
    // +   original by: Brett Zamir (http://brett-zamir.me)
    // +      input by: travc
    // +      input by: Brett Zamir (http://brett-zamir.me)
    // +   bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +      input by: Ratheous
    // +      reimplemented by: Brett Zamir (http://brett-zamir.me)
    // %        note 1: Please be aware that this function expects to decode from UTF-8 encoded strings, as found on
    // %        note 1: pages served as UTF-8
    // *     example 1: rawurldecode('Kevin+van+Zonneveld%21');
    // *     returns 1: 'Kevin+van+Zonneveld!'
    // *     example 2: rawurldecode('http%3A%2F%2Fkevin.vanzonneveld.net%2F');
    // *     returns 2: 'http://kevin.vanzonneveld.net/'
    // *     example 3: rawurldecode('http%3A%2F%2Fwww.google.nl%2Fsearch%3Fq%3Dphp.js%26ie%3Dutf-8%26oe%3Dutf-8%26aq%3Dt%26rls%3Dcom.ubuntu%3Aen-US%3Aunofficial%26client%3Dfirefox-a');
    // *     returns 3: 'http://www.google.nl/search?q=php.js&ie=utf-8&oe=utf-8&aq=t&rls=com.ubuntu:en-US:unofficial&client=firefox-a'
    // *     example 4: rawurldecode('-22%97bc%2Fbc');
    // *     returns 4: '-22—bc/bc'

    return decodeURIComponent(str);
}